JPS6312103B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a phenolic resin molding material. In general, phenolic resins are widely used as molding materials because they have excellent moldability, mechanical performance, physical performance, and especially heat resistance, considering their price. However, phenolic resins generally have brittle properties and have the disadvantage of poor impact resistance. A method is known in which a plasticizer or rubber is blended to compensate for this drawback. However, they have various drawbacks, such as poor compatibility with phenolic resins, making it impossible to obtain uniform and tough cured products, significantly lowering heat resistance, and poor workability during blending. The present inventors prepared a butadiene polymer containing an amide group, obtained by reacting a maleic anhydride-added butadiene polymer with ammonia, by mixing it with a novolak-type phenolic resin and a curing agent such as hexamethylenetetramine, and curing it. It has been found that a phenolic resin for molding can be obtained which has excellent workability, impact resistance, and heat resistance. That is, in the present invention, the number average molecular weight is 300 to 300.
5 to 200 parts by weight of a butadiene polymer containing an amide group obtained by reacting a maleic anhydride adduct of a butadiene polymer, copolymer, or mixture thereof with ammonia, and 100 parts by weight of a novolak type phenolic resin. and hardener 5
It is a phenolic resin composition containing ~40 parts by weight as an essential component. Next, the present invention will be explained in detail. The raw butadiene polymer used in the present invention may be a butadiene homopolymer with a number average molecular weight of 300 to 10,000 or a butadiene copolymer with a butadiene unit content of 50% or more, and may have any molecular structure. . For example, butadiene is homopolymerized in a hydrocarbon solvent using an alkali metal such as lithium or sodium or an organometallic compound thereof as a catalyst, or copolymerization of butadiene and styrene, etc. with a vinyl monomer, or butadiene and isoprene. Preferably used are those copolymerized with diolefins such as , piperylene, and the like. Also preferably used are butadiene monopolymerized or copolymerized with an alkali metal such as sodium as a catalyst in a polar solvent such as tetrahydrofuran using a polycyclic aromatic compound such as naphthalene or anthracene as an activator. Furthermore, butadiene polymers or copolymers obtained by using a coordination anion polymerization catalyst, and polymers obtained by telomerizing butadiene etc. with a radical initiator can also be used in the same way. . The maleic anhydride adduct of the butadiene polymer or copolymer or mixture thereof in the present invention can be produced by a conventionally known method of reacting the above-described butadiene polymer or copolymer with maleic anhydride at a temperature of 100 to 300°C. . It is also possible to adopt a method of adding a small amount of phenylene diamines, pyrogallols, naphthols, etc. to prevent the gelation reaction when carrying out the addition reaction. The amount of maleic anhydride added is usually 0.05 to 0.6 mol, preferably 0.1 to 0.5 mol, but up to 1.0 mol can be added per 100 g of the butadiene polymer or copolymer. A butadiene polymer containing an amide group is obtained by reacting a maleated butadiene polymer with ammonia. Ammonia can be used in the form of ammonia water or ammonia gas. The amount of ammonia used is the molar ratio to the succinic anhydride group.
0.2 to 3.0 mol is preferably applied. The amidation reaction can be carried out at 0 to 150°C. This reaction can be carried out either in the presence or absence of a solvent, and when a solvent is used, inert hydrocarbon compounds, ethers, etc. are preferred. The novolac-type phenolic resin used in the present invention is usually obtained by condensation at a formaldehyde/phenol molar ratio of around 0.9 using an inorganic or organic acid as a catalyst by a conventionally known method. As the curing agent, hexamethylenetetramine can be preferably used, but curing agents that are normally used for curing phenolic resins can also be used. As described above, the present invention includes a maleated butadiene polymer, a novolak type phenol resin, and hexamethylenetetramine as essential components. In the present invention, 5 to 200 parts by weight of a butadiene polymer derivative, preferably 15 to 100 parts by weight, or 5 to 40 parts by weight of a curing agent, preferably 7 to 20 parts by weight, are used for 100 parts by weight of novolak type phenolic resin. can do. In addition to these, the composition of the present invention requires fillers such as wood flour and asbestos, water, plasticizers such as furfural, accelerators such as magnesium oxide, lubricants such as stearic acid groups, coloring agents, and modifiers such as hiker. It is blended accordingly. These mixtures can be performed by a conventionally known method. That is, the mixture is premixed in a blender, kneader, etc. and then subjected to a hot rolling process. The sheet material taken out from the roll is crushed and used as a molding material. The present invention will be specifically explained below using synthesis examples and examples. Synthesis Example 1 1000 g of a butadiene polymer with a number average molecular weight of 800 and a vinyl bond of 56% synthesized by polymerizing butadiene using a sodium catalyst and 389 g of maleic anhydride were reacted at 195°C for 5 hours in the presence of 3c2 g of antigen. A maleated butadiene polymer having an acid value of 160 mg KOH/g was obtained. 1000g of this maleated butadiene polymer and 1000g of tetrahydrofuran
g was placed in a 3-separable flask equipped with a reflux condenser, heated to 50℃, and mixed with 25% ammonia water while stirring.
194 g was added dropwise over about 30 minutes. 50℃ after completion of dripping
After continuing the reaction for 1 hour, the temperature was raised to 80°C.
Tetrahydrofuran and water were distilled off under reduced pressure to obtain an amide group-containing butadiene polymer that was solid at room temperature. Example 1 Formaldehyde per mole of phenol
A 35% formalin aqueous solution containing 0.85 mol was added, and the reaction was first carried out at reflux temperature for 60 minutes in the presence of oxalic acid (0.4 mol % based on phenol), and then hydrochloric acid (0.2 mol % based on phenol) was added and reacted for 35 minutes. I let it happen. After dehydration, the mixture was heated to 115°C to obtain a novolak type phenolic resin. Next, each raw material was mixed as shown below. Novolac resin 100 parts Butadiene polymer containing amide groups from Synthesis Example 1 30 parts Wood flour 110 parts Stearic acid 2 parts Lime 2 parts Nigrosine (alcohol soluble) 2 parts Furfural 5 parts Hexamethylenetetramine 12.5 parts The above mixture. The mixture was mixed and then kneaded with a heated roll at 80 to 120°C to obtain a sheet-like product. Next, this sheet-like material was crushed to obtain a phenolic resin molding material. Table 1 shows the results of the performance test of this phenolic resin molding material. Comparative Example 1 A phenolic resin molding material was obtained in exactly the same manner as in Example 1 except that 30 parts of Hiker powder was added in place of the amide group-containing butadiene polymer of Example 1. The results of this performance test are shown in Table 1. Note that bending strength, impact strength, heat resistance, and insulation resistance were each measured based on JIS-K6911.

[Table] As is clear from the table, the molded products molded using the molding material of the example showed equivalent performance in insulation resistance and impact strength, and had better bending strength and heat resistance than the conventional product containing hiker powder. Are better. Workability and moldability were also superior to those of the comparative example.

Claims (1)

[Scope of Claims] 1. A butadiene polymer containing an amide group obtained by reacting a maleic anhydride adduct of a butadiene polymer, copolymer, or a mixture thereof having a number average molecular weight of 300 to 10,000 with ammonia. A phenolic resin composition containing 5 to 200 parts by weight, 100 parts by weight of a novolak type phenolic resin, and 5 to 40 parts by weight of a curing agent as essential components. 2. The composition according to claim 1, wherein the curing agent is hexamethylenetetramine.